Three. You'll want to notice the letters coming up with the Zombies. In degree 1 just one letter will come with a Zombie, but the number of letters will increase at higher levels respectively. You have to strike the letters to reduce the zombie. Zombie Typing Game is a fun https://reidqjofw.thezenweb.com/the-single-best-strategy-to-use-for-zombie-typing-browser-version-77550021